Marijuana is up to 20 times more potent than it was 40 years ago and most pregnant women who use the drug are totally unaware that it could harm their unborn child before they even know they are pregnant.

Writing in the journal Drug Testing and Analysis, American researcher’s state the argument that marijuana is a harmless drug is no longer valid due to the emergence of ‘high potency’ marijuana and synthetic marijuana which pose a potential real threat for pregnant women.

They also express concerns that marijuana’s increased popularity among teenagers and young adults could put this group at higher risk.

“The emergence of bioengineered crops and novel, medicinal marijuana strains, means that marijuana is no longer what it used to be in the 1970′s and early 1980s’: some new, high potency strains, including some medicinal marijuana blends such as ‘Connie Chung’ and many others, contain up to 20 times more THC, the psychoactive constituent of marijuana, than did ‘traditional’ marijuana from the 1970′s and early 1980′s ” explains co-author Dr. Delphine Psychoyos from the Center for Genetic and Environmental Medicine at Texas A&M University. “Furthermore, with the emergence of dispensaries and Internet websites, high potency marijuana and Spice products are now readily available to the general population.”

Spice products, a prominent brand of ‘synthetic marijuana’, or ‘fake weed’ mixtures, contain extremely potent THC analogues, also called ‘synthetic cannabinoids’, such as AM694 (found in Euphoric Blends Big Band and others) and HU210 (found in Spice Gold), both of which are 500-600 times more potent than marijuana’s THC.

“The THC contained in ‘high potency’ marijuana and the potent THC analogues contained in Spice products and other brands of ‘synthetic marijuana’, are potentially harmful to embryonic development, as early as two weeks after conception. This is because these psychoactive chemicals have the ability to interfere with the first stages in the formation of the brain of the fetus; this event occurs two weeks after conception, earlier than before signs of pregnancy appear. By the time a woman realises she is pregnant and stops taking these substances it may already be too late for her unborn child. ”

“Given that marijuana is the most widely used illicit drug by pregnant women worldwide – one study estimates the rate is as high as 20 per cent – this is a major issue.”

Recent research from the past 5 years has shown that marijuana exposure during pregnancy has been associated with anencephaly, a non-sustaining life condition where a large part of the skull or brain is absent, neurobehavioral deficiencies, such as attention deficit hyperactivity disorder, learning disabilities and memory impairment in toddlers and 10 year olds, as well as neuropsychiatric conditions, including depression, aggression and anxiety, in teens.

“The problem is that many women who are pregnant, or are planning to become pregnant are totally unaware of this increased potency and the risks they pose,” says co-author Dr. Delphine Psychoyos. “This is because many websites on mothering and pregnancy, and those run by pro-marijuana advocacy groups, base their discussions on data collected prior to 1997, when no detrimental affects on pregnancy had been reported; It is important to note here that prior to 1997, pregnant women were mostly exposed to low potency, ‘traditional’ marijuana, which was the common form of marijuana in the market in the 1970′s and early 1980′s.”

“Marijuana has regained its popularity from the 1970s, especially among teens and young people, and has established social and cultural status as the most popular drug of abuse. Yet, like pregnant women, these young users probably have no idea of the significant increase in potency over the past four decades. ”

The researchers are calling for greater awareness among pregnant women about the availability of highly potent marijuana and synthetic cannabinoids such as those found in Spice products, and the risks that they can pose to their unborn child, even before their pregnancy has been confirmed.

They highlight the need to revise U.S. government bills and legislation to take account of the development of synthetic cannabinoids, such as those found in Spice and in new psychoactive substances that are based on cannabinoid research chemicals; They also question whether there is a need to put high potency marijuana in the highest category, if marijuana is to become legalised in America, based on its medical applications.

The authors also stress that teenagers and young people need to be more aware of the health risks of high potency marijuana, of synthetic cannabinoids found in Spice and other brands, and of synthetic cannabinoid research chemicals sold as designer drugs on various non DEA-regulated websites.